I own an '68 , '67 and a '65 . The '67 first year ohc last year dual sprockets. My late father upgraded the '67 to dual range one sprocket . I built a '68 up for a friend from spares , it has dual range and dual sprockets. The weak link with these bikes is the fuel tank leaking at the mounts . Next the muffler is always going to be rotted out to some extent. The front dampeners are not , and since you can't rebuild them or purchase new ones never will be. I doubt they ever worked . 50/50 the rectifier is bad along with all the light bulbs and the battery which if not in top shape will cause the bike to run poorly . I have much more to share . I have owned many many 90's . I ride my '68 year round . It has been places it was never intended to go . Great bike !